Article and method for forming a denture



Aug. 12, 1969 s. SCHNEIDER ET AL 6 5 ARTICLE AND METHOD FOR FORMING ADENTURE 2 Sheets-Sheet 1 Filed May 2, 1967 INVENTORS ymrz ATTORNEY g-1969 s. SCHNEIDER ET AL 3,460,252

ARTICLE AND METHOD FOR FORMING A DENTURE Filed May 2, 1967 I 2Sheets-Sheet 2 ATTORNEY United States Patent Int. Cl. A61c 9/00 US. Cl.32-2 12 Claims ABSTRACT OF THE DISCLOSURE An article and method forforming a denture including a pro-formed tray having a set of teeththerein. A moldable resin is poured into the tray having a set of falseteeth therein, and the tray is placed into an envelope.

The user places the envelope into his mouth and by applying pressure tothe resin through the envelope, a final denture is formed.

The art of making dentures for individuals who require false teeth hasbeen carried on for many years. The process requires many hours oftedious work by a skilled technician in order to make a denture which istailored to an individualsmouth. The-time elapsed between the firstvisit to a dentist and the fitting of a finished denture is on theaverage four to six weeks.

Initially the individual must see a dentist who places an alginate gelor similar moldable plastic in a metal tray from which an impression ismade of thepatients gums and roof of the mouth or palate if an upperdenture is required. The impression is sent to a dental technician whomakes a plaster cast of the gums and palate and places the cast in anarticulator. A wax base plate is poured on and false teeth arepositioned in the wax. The wax denture is returned to the dentist whotrys it on the patient. The dentist makes corrections and returns thetrial denture to the technician. The technician then begins the longlaborious task of making a denture which requires many steps well knownin the art and takes many hours and requires expensive, specializedtools.

The technician uses plaster of paris and resins which tend to sticktogether, and the plaster must be carefully cleaned from between thefalse teeth or they can be scratched. The finished mold must be sandedand polished and a great deal of dust is produced in the laboratorycreating a very unsatisfactory environment.

Our invention dispenses with the use of plaster as a molding materialand the inherent difiiculties concomitant therewith. For example, theprocess of mixing the plaster solution, pouring, fiasking and heatingare eliminated enitrely including the arduous task. of removing theplaster from the finished denture which can ruin an otherwise completeddenture if one is not careful.

The present invention seeks to overcome the obvious expensive andarduous task of making. a denture and to dispense if desired with theservices of a dentist and technician. Any unskilled person can make asatisfactory denture by utilizing the principles of our invention.Basically, our invention contemplates using a moldable resin which ispoured into an adjustable and flexible tray having false teeth placedtherein and formed to fit into an average size mouth. The traycontaining the resin is placed in an envelope. The user places theenvelope containing the tray in his'mouth and by exerting oral muscularpressure upon the resinous mass, a denture is formed which is identicalto the contour of the gums and palate. The latter procedure requiresapproximately two hours including curing time as compared with fifteenhours including curing time by a skilled technician and "ice notincluding time lost by sending the denture between the technician anddentist for adjustment.

It is an object of this invention to enable an unskilled person to formhis own dentures and more specifically to form a denture requiring fewsteps.

It is a further object of this invention to provide a tray which isadjustable to fit a persons mouth.

It is still a further object of this invention to utilize materialswhich are compatible and do not stick together.

It is another object of this inventionto enable a person to make adenture that will require little time to fabricate.

It is still another object of this invention to enable a denture to bemade without using plaster as an element in the mold. a

It is still a further object to provide a method for forming a denturein which the oral tissue does not contact any injurious substance usedin making the denture.

It is yet another object of this invention to maintain teeth properlyspaced and held together in a tray by using a silicone rubber or othersuitable binder.

It is an additional object of this invention to provide an envelopewhich permits harmful vapors to escape from the oral cavity andprecludes the oral tissues from coming into contact with the resin orvapors.

It is still another object of this invention to provide a method formaking a denture which requires few parts and is simple to fabricate andinexpensive to manufacture.

Additional objects will become apparent to those skilled in the art fromreading the ensuing specification, drawing and claims in which we havedisclosed a preferred embodiment of our invention.

The attached drawings illustrate a preferred embodiment of our inventionin which:

FIG. 1 is a perspective showing an upper tray;

FIG. 2 is a perspective showing a lower tray;

FIG. 3 is a section taken along the line 33 in 'FIG. 1;

FIG. 4 is a section taken along the line 4-4 of FIG. 2;

FIG. 5 is a view showing the tray having severed portions thereon;

FIG. 6 is a view showing the tray in elevation and partly in sectiontaken along the line 6-6 in FIG. 5;

FIG. 7 is a top view of a tray having resin therein and a cutawayshowing false teeth embedded in said resin;

FIG. 8 is a view taken along the line 88 in FIG. 7;

FIG. 9 is a perspective showing a tray in an envelope.

FIG. 10 is a view taken along the line 1010 in FIG. 9;

FIG. 11 is a top view of a finished denture within a tray;

FIG. 12 is a view taken along line 12-12 in FIG. 11, and

FIG. 13 is a side elevation partly in section showing false teeth moldedwithin a denture which has cured.

Referring to FIGS. l-4, there is shown a tray 20 which is preferablyformed of a thin flexible plastic in the family of polyethylene orpolypropylene polymers or co polymers. The tray can be vacuum formedfrom a sheet of material. The tray could also be formed by any otherknown method such as injection or blow molding. The tray 20 is used formaking an upper denture and the tray 22 is used for making a lowerdenture.

Reference will now only be made to the upper tray 20 and since the tray22 is similar like parts will be referred to with like numbers.

The tray 20 has weakened lines 24 conveniently placed thereon preferablyin the form of triangular lines; however, any configuration can be used.The weakened lines are to be severed which permits the tray to bemodified in size. Thus, the tray can be adapted to any size month bycutting the weakened lines and squeezing or spreading the tray.

An adhesive tape 26 can be used to lock the severed por-.

tions together when the proper size has been made to fit the mouth ofthe particular user, or if a portion is removed to make the traysmaller, the tape can be used to fill the void. The weakened lines 24are preferably placed in the palate portion 28 on the upper tray 20. Thepalate portion 28 is shaped to conform to the average persons mouth andby simple adjusting after the weakened lines have been severed will fitany mouth. The weakened lines 24 are placed on the inner wall on thelower tray 22.

The upper tray 20 has an outer flexible wall 32 which is generallyU-shaped. The palate portion includes an inner flexible wall 31. Theinner and outer wall portions are interconnected along the U-shapedbottom portion of the tray.

The lower tray 22 also includes a flexible outer wall 32 and a flexibleinner wall 31 which walls are interconnected along the U-shaped bottomportion of the tray.

The gum-receiving portion 30 which lies between the outer and innerwalls 31 and 32 comprises a trough 34 which is designed to receive falseteeth 42 and a persons gums. The trough 34 is relatively narrow at theforward portion 36 of the tray and gradually increases in width alongthe side portions 38 of the tray as shown in FIG. 5. Thus, the frontteeth which are relatively narrow are snugly held in the tray and therear teeth which are wider are snugly held in the wider portion of thetray.

Impressed within the trough 34 of the tray 20, as by molding or anyother suitable method of indicating, is indicia or cavities in the formof spaced depressed portions 40. The latter indicia 40 indicates to theuser the proper placement of the false teeth 42 within the tray 20 priorto making the denture. Each tooth is thus snugly held within adepression and because the trough 34 increases gradually in width, theteeth 42 are supported and cannot readily move out of place. Thus therecan be no leaning or turning movement of the teeth and perfect alignmentis always insured.

The false teeth 42 are firmly and immovably held within the traypreferably with a rubber 44 of the silicone type to which a catalystsuch as dibutyl tin dilaurate has been added. Any other binder materialcan be used to hold the false teeth together in the mold such as rubberof the nonsilicone type, glue, wax or a mechanical means such as a bracecan hold the teeth together. The purpose of the silicone rubber 44 orother type binder is to hold the teeth within the tray in proper spacedrelation to each other and to avoid coverage by the denture of the teethresin that would result in an extra cleaning step. Actually a denturecan be made without the binder.

When the silicone rubber mix and catalyst are used, the mix is poured orinjected into the trough 34 of the trays 20 and 22. The false teeth 42are then placed into the mix as indicated by the indicia 40 on thewalls, and the rubber 40 is allowed to cure whereupon the teeth will beimmovably held in the tray. The rubber 44 will not adhere to the tray orfalse teeth firmly and is easily separated therefrom after the denturehas been completed because of the nature of the materials.

The silicone rubber 44 or other binder could be dispensed with bymolding pockets or depressions within the tray which firmly grips andmaintains the teeth closely adjacent to each other during the moldingprocess. The tray is now ready to receive the denture material 46.

The denture material 46 is a cold curing pigmented mixture consisting ofa powder and a liquid. The powder is a polymer preferably of the acrylicfamily. Certain copolymers can also be used consisting of vinyl resinsor styrene. The liquid material is preferably an acrylic monomer ormixture of acrylic monomers such as methyl methacrylate and butylmethacrylate. These materials have been used in the prior art as denturerepair materials. The powder and liquid contain small quantities ofknown catalysts which interact to cause hardening of the mixture withina short time without any external heat source.

The powder and liquid are thoroughly mixed together to form a soft,puttylike, resinous slurry which is poured into the denture forming tray20. If desired, a shim 48 can be loosely attached to the upper tray inorder to control the thickness of the palate portion 28 of the denturewhich is preferably between 1 to 3 millimeters in thickness. The denturecan be made without the shim, however. The resin mixture covers thefalse teeth up to the binder 44 and the entire interior of the tray 20circumscribed by the outer wall 32. i

Since the gum tissue is sensitive to the resin 46 the resin filled trayis preferably covered with a thin flexible material such as plastic orcloth having a low permeability to the monomer of the denture material.The protective covering can be placed over the gums and palate in theusers mouth or can cover the resinous material in the upper and lowertray 20. A preferred protective covering is a material comprising apolyvinylidene chloride film in the form of an envelope 50 as depictedin FIG. 9. Three sides of the envelope are sealed and one side 52 isopen. The tray 20 is inserted into the envelope 50 with the frontportion of the tray 20 facing the open end 52 of the envelope to allowvapors to escape outside the mouth cavity while the opposite closed endprevents vapors from entering the mouth cavity.

The tray 20 and envelope 50 unit, generally denoted by numeral 54 isthen placed in the mouth so that the gums are placed within the confinesof the walls 32 of the tray 20. The user then exerts pressure on theunit 54 by biting into the resinous mass and pressing against the palateportion 28 of the tray with the tongue. A pad 56 shown in dotted linesin FIG. 12 may be inserted between the tongue and the palate portion 28of the upper tray in order to obtain a better forming pressuretransfered to the resinous denture material. The pad 56 can be a foamrectangular or square cube. The unit 54 is kept in the month until theresin mixture feels warm to the senses which entails approximatelyfifteen (15) minutes. The unit 54 is then carefully removed from themouth by releasing the previously applied pressure. The denture materialhas now been molded to precisely the shape of the gums and follows thecurvature of the roof of the mouth for the upper denture. The resinousmass is allowed to cure for an additional time of approximately ten tofifteen minutes. The upper and lower dentures can be made at the sametime or separately.

The user, thereupon, removes the upper or lower tray 20 or 22 from theenvelope 50. The tray because it is flexible is merely bent away fromthe curved denture and the resin does not adhere to the flexible tray.The rubber 44 is easily peeled away from the false teeth and the tray.The denture is now complete except for smoothing any rough edges whichmay have formed. The latter is simply accomplished with a piece ofsandpaper. When the completed denture 58 is placed over the gums aperfect fit results without having had to resort to the tedious,expensive and time consuming method of the prior art. If desirable theperson can use a liner of soft material such as a gel type materialbetween the denture and the gums for even greater adherence of thedenture plate to the gums.

We claim:

1. An article for molding in a single operation a completed denturecomprising,

(a) an outer-flexible wall extending upwardly and forming a U-shapedperiphery,

(b) an inner flexible wall spaced from said outer wall and extendingupwardly,

(c) a connecting portion joining said inner and outer walls therebyforming a trough open at one end thereof and closed at said connectingportion,

(d) said connecting portion having cavities therein in the form of teethfor indicating the location of false teeth whereby said teeth areproperly placed and firmly held within said trough whereupon saidarticle which is adapted to have a moldable substance therein can beinserted into a users mouth to form a completed denture. 2. An articlefor molding a denture as defined in claim 1 in which said connectingportion is narrow at the front portion of the U-shaped peripheral walland gradually in creases in size to a wider portion at the rear of theU- shaped peripheral wall.

3. An article for molding a denture as defined in claim 1 in which saidcavities comprise a plurality of spaced apart depressions adapted toreceive false teeth therein.

4. An article for molding a denture as defined in claim 1 in which saidinner and outer walls have a moldable denture forming materialtherebetween and a thin, flexible protective covering means over saiddenture forming material adapted to prevent gum tissue from directlycontacting said denture forming material.

5. An article for molding a denture as defined in claim 1 in which atleast one of said walls has means thereon to enhance severing said wallat a predetermined portion whereby the size of said article can beadjusted to fit said oral cavity.

6. An article for forming a denture as defined in claim 1 including ashim on said inner wall to control the thickness of the denture.

7. An article for molding a denture comprising,

(a) an outer, flexible, U-shaped upstanding wall,

(b) an inner, flexible, upstanding wall connected to said outer wall, onone side thereof,

(c) said upstanding walls forming a trough therebetween for thereception of false teeth,

(d) at least one of said Walls having means thereon to enhance severingthe wall in a predetermined place on said wall whereby the walls can beadjusted in size to fit a persons mouth.

8. An article for forming a denture as defined in claim 7 in which anadhesive tape joins the severed portion of said Wall to maintain thesevered portions in a fixed configuration.

9. An article for forming a denture as defined in claim 7 comprising,

(a) a denture forming material between said inner and outer walls,

(b) a thin, flexible protective covering means over said denture formingmaterial adapted to prevent gum tissue from directly contacting saiddenture forming material.

10. An article for forming a denture as defined in claim 9 in which saidthin, flexible protective covering means over said denture formingmaterial comprises a closed envelope having an opening therein.

11. A method for molding a denture comprising the steps of:

(a) placing a moldable resin in a tray having cavities in the form ofteeth therein and adapted to be placed in a users mouth,

' (b) placing protective means between the resin and gum tissue in theusers mouth,

(c) inserting said tray and resin into the users mouth,

(d) applying pressure to said resin through said protective means.

12. A method for molding a denture as defined in claim 11 includingplacing a pad between the tray and the users tongue.

References Cited UNITED STATES PATENTS 584,345 6/1897 Gilmer 3222,341,155 2/1944 Myerson 32-17 2,446,298 8/ 1948 Nelson 32-2 2,696,66812/1954 Fox 32-19 ROBERT PESHOCK, Primary Examiner U.S. Cl. X.R. 32-17

